Dimon's back at it: Bitcoin buyers are "stupid"

With Bitcoin soaring almost 100% from the bottom of the sharp selloff following Jamie Dimon's slam of cryptocurrencies as "frauds" exactly one month ago today, bitcoin was one of the more popular topics on today's earnings call, where JPMorgan CFO Marianne Lake confirmed what everyone already knew, namely that the technology underlying bitcoin-blockchain-is something the bank is investing in, and is "very optimistic" about the underlying technology of distributed ledgers and blockchain.

Bitcoin has again hit a new record-high valuation, tipping $5,200 (£3,900) despite experts continuing to express scepticism about the cryptocurrency's popularity. "The only value of bitcoin is what the other guy'll pay for it", Dimon said.

BlackRock CEO Larry Fink took a shot at cryptocurrency bitcoin on Friday, calling it an "index of money laundering".

Dimon had lots more to say: He said governments will "crush" the currency one day, mostly by regulated digital currencies out of existence. I've also told people that it can trade at $100,000 before it trades to zero. He reportedly said that bitcoin is "great" for criminals, and that - in a refrain from yesterday - that it would be the last time he would comment on the subject.

I could care less what bitcoin trades for, how it trades, why it trades, who trades it.

So far, Dimon's screeds against cryptos have led to retreats in bitcoin's price, followed by sharp moves higher, to such an extent that investors genuinely betting for its price to fall might hope that he holds to his vow to stay silent this time.